抄録
The effect of geometric surface structure of glidant on flowability of pharmaceutical fillers and the factors that determine the optimum amount of glidant added were investigated with AFM and IR spectroscopy. Several types of silica particles were used as a glidant in preparing the mixture of lactose and microcrystalline cellulose. The flowability of mixed powder was evaluated with Can's index. As a result, it was found that the flowability and the optimum mixing ratio depend on the geometric surface structure of glidant. AFM study showed that the porosity of silica particles plays an important role in determining flowability through the reduction in adhesion force. Furthermore, IR study suggested that the optimum mixing ratio is closely related to the surface coverage of filler with glidant. The optimum mixing ratio of porous silica is smaller than that of nonporous silica since the surface coating with porous silica is completed at a lower mixing ratio.